A number of naturally-occurring C8-pseudoguaianolides have been shown to possess anti-neoplastic activity. The total synthesis of such compounds, e.g. aromatin, radiatin and fastigilin C, will provide them in sufficient quantities for additional biological testing and simultaneously generate synthetic analogs for additional biological evaluation. Flexibility in our synthetic plan will provide options for preparing new biologically-active pseudoguaianolides as they may become isolated from bioassayed plant extracts and characterized.